Calibre database missing or corrupted

[zamorano]

CC connected to Dropbox.
I get again and again the message even after regenerating anew the database in Calibre. Even after deleting all data in CC before retrying.

[stumped]

you need to say what version of CC on what device

and you need to check that the library IS in dropbox, including a file called metadata.db. if that file is missing, you will see this type of error

how are you adding the library to dropbox ?

[zamorano]

CC version 5.4.4.8 on Android WAS-LX1A 8.0.0.390 (C432)
Yes, the library (metadata.db) IS in Dropbox
The library is added to Dropbox by Dropbox running on Windows-10 in my portable computer

[stumped]

ok - its unlikley to be a CC app bug.
I have the same CC version working Ok with dropbox.
is that metadata.db the same file as the one in your source library. use a file comparison utility or at least compare bytes size
try replacing it with a known good copy
and do a files and folders count of what is in dropbox vs what is in your local source library
the recommended way to add to dropbox is via the dropbox app: put the files & folder into the local dropbox x folder and wait for dropbox to completely sync.
adding via a browser in windows is NOT reliable.

In parallel you could also try this test. Install the free calibrebox app from play store & link it to your dropbox. Does that app also say database corrupt or is it happy to transfer books...
if 2 different apps say corrupt database then you almost certainly have a corrupt database.
if not, then at least you have a workaround while you pursue the issue with CC developers

[ottischwenk]

Originally Posted by stumped

ok - its unlikley to be a CC app bug.

I is a CC bug.
metadata.db in Cloud is identical with original.

[stumped]

Originally Posted by ottischwenk

I is a CC bug.
metadata.db in Cloud is identical with original.

excuse me, but you are not the OP, how can you know if HIS metadata.db is same as HIS original file ???
unless you are posting from two usernames, which is not allowed

I know that box , not dropbox gave that error, fixed in 4.4.9 but no one else here has reported a dropbox error, just missing covers

if OP is editing a live library in dropbox, while dropbox does background syncs then all bets are off. there's no fix for failure to read any of the calibre in cloud/on network drive warnings.

[PMrev]

Originally Posted by zamorano

CC version 5.4.4.8 on Android WAS-LX1A 8.0.0.390 (C432)
Yes, the library (metadata.db) IS in Dropbox
The library is added to Dropbox by Dropbox running on Windows-10 in my portable computer

Try this article for setting up your Calibre library correctly to work with CC.

https://calibrecompanion.co/how-to-dropbox-onedrive/

[ottischwenk]

Originally Posted by stumped

excuse me, but you are not the OP, how can you know if HIS metadata.db is same as HIS original file ???
unless you are posting from two usernames, which is not allowed

It is very simple!
I got the same error and My metadata.db ist the same as MY original file.

I know that box , not dropbox gave that error, fixed in 4.4.9 but no one else here has reported a dropbox error, just missing covers

And login problems - eg to OneDrive.
And it happens in 5.4.4.8 - how did you get X.4.4.9? I could not find this version.
And in OneDrive: everytime after new boot i get an error when connecting to OneDrive.
I had to close CC, clean memory, start again and have to enter login data.

[stumped]

Originally Posted by ottischwenk

It is very simple!
I got the same error and My metadata.db ist the same as MY original file.And it happens in 5.4.4.8 - how did you get X.4.4.9? I could not find this version.

same error message can have multiple causes.
in your case, with box, it was caused by CC using the wrong path
in OP case, its probably caused by a bad upload method to dropbox which did not preserve subfolder structures ( that will happen if drag and drop to web site is used )

4.4.9 reached my play store yesterday

[ottischwenk]

Originally Posted by stumped

4.4.9 reached my play store yesterday

Till now I didnt get it!

[zamorano]

The metadata.db in Dropbox seems to be identical to the one in my Android phone and my Android tablet (Samsung). It fails in my tablet for the same Calibre library too.
Y maintain two other Calibre libraries (all with the same procedures) and it fails only with one of them (in both devices, phone and tablet).
I have one conjecture:
- CC maintains one local copy of metadata.db in the device (say, in the phone)
- CC compares the local copy with the one in Dropbox to decide whether it should update its local copy. For that purpose it first reads the local metadata.db, then downloads the one in the Dropbox server.
- imagine the Dropbox metadata.db is corrupted when downloaded by CC. Because, for instance, it is being just then updated by Dropbox from the Calibre metadata.db in my laptop.
- the next time CC tries to compare its local copy with the one in the Dropbox server, it finds its local copy corrupted. And this is what CC notifies. ¿Could the CC local metadata.db (in the phone) be the guilty? ¿Even if the metadata.db in the server is correct (correctly reconstructed by Calibre in my computer and correctly copied by Dropbox into his server)?

Knowing the decision procedure CC uses to decide whether is should download the metadata.db from the Dropbox server and what exactly the notification "missing or corrupted" means (to which metadata.db it refers to) should clarify is this conjecture is sensible or not.

Could'nt it be a CC bug if the metadata.db instances in my computer and in the Dropbox server are identical? It probably is, I would think.

[zamorano]

"The metadata.db in Dropbox seems to be identical to the one in my Android phone and my Android tablet (Samsung). It fails in my tablet for the same Calibre library too."

What I intended to say is : The metadata.db in the Dropbox server semms to be identical to the one in my laptop. CC fails both in my Android phone (Huawei) and my Android tablet (Samsung.

[stumped]

Originally Posted by zamorano

"The metadata.db in Dropbox seems to be identical to the one in my Android phone and my Android tablet (Samsung). It fails in my tablet for the same Calibre library too."

What I intended to say is : The metadata.db in the Dropbox server semms to be identical to the one in my laptop. CC fails both in my Android phone (Huawei) and my Android tablet (Samsung.

what about the subfolder structure in dropbox. right click properties to get a count of both files and folders.
does that match your source calibre library which is hopefully on a non-cloud, not-networked PC drive.

i found out the hard way that if you add files within subfolders to a dropbox folder via browser, the files do get uploaded but not always in the correct subfolders , thus you get a corrupt library as books are not where metatdata.db thinks they are

also, test with CC connected via content server and/or as wireless direct to your laptop over LAN,

there are 3 components in play: the calibre library installation, the cloud copy , and the CC app. you need to prove which one is faulting. best way is with tests that only use 2 out of 3 components

please try my suggestion of testing the alternative calibrebox app to help establish if it is an app problem or a dropbox issue

[zamorano]

1) How do I use Calibre (+ Dropbox)
I have Calibre installed in may Windows 10 laptop. I create the Calibre library(ies) using Calibre and add books always and only using Calibre. I do not touch the file structure of the Calibre library(ies) but using Calibre.
I place the library(ies) at creation in the Dropbox area of my file structure in Windows. The books I add are always placed by Calibre within this area.
(I should not use Calibre while Dropbox is on, but I did it sometimes until I noticed it should not be done -for understandable reasons-. This could lead to a non-orthosox -corrupted?- metadata.db. But notice that after having the problem I recreated metadata.db using Calibre, as supported by Calibre)
2) How do I use Dropbox
Dropbox is the only that creates and maintains the file structure in its server. I never touch directly this file structure in the Dropbox server. I merely modify (as already said) the file structure in the Dropbox area of the file structura in my laptop through Calibre.
3) How do I use CC
I have CC installed in my phone and in my tablet. From both I occasionally ask CC to connect to Dropbox and download some book from my library

Notice that I have used exactly the same procedures with two separated libraries for years and with an additional one for months. And only recently found the problem with just one of the three libraries.

I had never problems with Dropbox in up- and down-loading files

Which is the "alternative calibrebox app"? How can I get it?

[zamorano]

metadata_Windows.db: as created by Calibre in my laptop
metadata_Dropbox.db: re-downloaded from the Dropbox server

https://www.dropbox.com/preview/meta...?role=personal